National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

N syndrome


Other Names:
NSX; Mental retardation, malformations, chromosome breakage, and development of T-cell leukemia
Categories:
The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 2608

Definition
N syndrome is characterised by intellectual deficit, deafness, ocular anomalies, T-cell leukaemia, cryptorchidism, hypospadias and spasticity.

Epidemiology
Three cases have been described so far.

Etiology
Mutations in DNA polymerase alpha, leading to increased chromosome breakage, may be responsible for the syndrome.

Genetic counseling
X-linked recessive transmission has been proposed.

Visit the Orphanet disease page for more resources.
Last updated: 11/1/2006

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 15 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal eyelid morphology
Abnormality of the eyelid
Abnormality of the eyelids
[ more ] 		0000492
Bilateral sensorineural hearing impairment 0008619
Cryptorchidism
Undescended testes
Undescended testis
[ more ] 		0000028
Global developmental delay 0001263
Hypospadias 0000047
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation
[ more ] 		0001249
Megalocornea
Enlarged cornea
0000485
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257
T-cell lymphoma/leukemia 0005517
Visual impairment
Impaired vision
Loss of eyesight
Poor vision
[ more ] 		0000505
Percent of people who have these symptoms is not available through HPO
Abnormality of chromosome stability 0003220
Hearing impairment
Deafness
Hearing defect
[ more ] 		0000365
Leukemia 0001909
Neoplasm 0002664
X-linked inheritance 0001417
Showing of 15 |
Last updated: 7/1/2020

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss N syndrome. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.